Osceola is a city in, and a dual county seat of, Mississippi County, Arkansas, United States. Located along the Mississippi River within the Arkansas delta, the settlement was founded in 1837 and incorporated in 1853. Occupying an important location on the river, the city's economy grew as steamboat traffic increased. Timber and cotton harvesting would develop, and the city experienced rapid growth and development throughout the early 20th century. The city's economy has since diversified to include a robust industrial sector. The population was 7,757 at the 2010 census.
During the prehistoric period, Osceola and Mississippi County was largely swampland, with dense forest cover. The area was inhabited mostly by Native American tribes under French and Spanish rule until the first American settlers arrived around the time of the Louisiana Purchase in 1803.
Initial white visitors to the area were speculators, hunters, and outlaws, but the remote region remained sparsely populated by settlers. An extremely intense New Madrid earthquake swarm, produced by the New Madrid Seismic Zone nearby in present-day Missouri, struck the area in 1811–1812.